After a family visit, stressed businesswoman Senga Wilson (Madeleine Stowe) is driving with her rebellious daughter, Nat (Mischa Barton), down an ominous highway in the middle of the night. After they pick up a weird teenage hitchhiker (Bijou Phillips), their journey goes awry. Nat decides to give her mom the slip and runs off with the hitchhiker at a rest stop. In a desperate search to find her daughter, Senga learns that Nat has been drawn into an evil cult.